DWS Treasury Portfolio Average Annual Total Returns - Institutional Shares [Member] - Institutional Shares - Return Before Taxes[Member] |
12 Months Ended | 60 Months Ended | 120 Months Ended | |
|---|---|---|---|---|
Jul. 28, 2026 |
Dec. 31, 2025 |
Dec. 31, 2025 |
Dec. 31, 2025 |
|
| Prospectus [Line Items] | ||||
| Average Annual Return, Percent | 4.17% | 3.16% | 2.09% | |
| Performance Inception Date | Dec. 17, 1991 |